JP2010138876A - Pump facility and method for operating the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain a stepwise start of draining of a plurality of vertical shaft pumps even when water flows rapidly into a water absorption tank, to make draining operation time for each vertical shaft pump uniform, and to unify the specification of each vertical shaft pump in a pump facility provided with a plurality of the vertical shaft pumps provided in the water absorption tank. <P>SOLUTION: In each vertical shaft pump 11, switching can be performed between: forcible operation in air in which a discharge valve 37 is closed, communication between a discharge port and a discharge pipe 23 is cutoff, a control valve 37 is opened, and a main shaft 25 is rotated by a driving mechanism 28 in a state of compressed air from a compressed air supply source filled in a casing 22; and normal operation in which the discharge valve 37 is opened, the discharge port is communicated with the discharge pipe 23, the control valve 37 is closed, and the main shaft 25 is rotated by the driving mechanism 28 in a state of the compressed air not being supplied from the compressed air supply source. In the vertical shaft pumps 11, operation is switched from the forcible operation in air to the normal operation sequentially according to a rise of the water level in the water absorption tank 20 detected by a water level detection means 46. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a pump facility and an operation method thereof.

  As conventional pump equipment, in order to start draining step by step (in order) to a plurality of preceding standby type vertical pumps according to the water level in the water absorption tank, a plurality of vertical pumps are arranged at different heights, A pump in which the impeller positions of the pump are shifted in the vertical direction is known (see Patent Document 1).

  In this pump facility, the water levels in a plurality of vertical pumps cannot be individually adjusted. Therefore, when rainwater suddenly flows into the water absorption tank, all the impellers arranged at different heights are submerged substantially simultaneously, and all the vertical shaft pumps start draining simultaneously. If all the vertical pumps start draining at the same time, the power supply equipment that supplies power to the drive mechanism of each vertical pump including the motor is adversely affected by sudden load fluctuations.

  Further, in this pump facility, the drainage operation time of the vertical shaft pump at a relatively low position is longer than that of a pump at a relatively high position. As a result, pump bearings, impellers, and the like that are relatively low in position are significant (decrease) compared to pumps that are relatively high in wear. Since it is necessary to replace the pump that has been reduced, the entire pump facility increases the period during which it cannot be operated, and more labor and cost such as pump replacement are required.

Furthermore, since the installation height of the impeller must be different in this pump equipment, it is necessary to use vertical pumps with different specifications in order to satisfy the space constraints in the height direction required for the equipment (machine). is there. Designing a plurality of vertical shaft pumps having different specifications is more costly than designing only one type of pump.
Japanese Patent No. 2136740

  The present invention provides a pump facility in which a plurality of vertical pumps are provided in a water absorption tank, so that even when water suddenly flows into the water absorption tank, a plurality of vertical pumps start draining step by step, and each vertical pump drains. The tasks are to make the operating time uniform and to unify the specifications of the vertical shaft pump.

  The first aspect of the present invention includes a water absorption tank into which water flows from the upstream side and a suction bell having a suction port that opens in the water absorption tank on the lower end side, while the discharge port connected to the discharge pipe is located on the upper end side. A plurality of vertical shaft pumps each having a casing provided in the casing, an impeller positioned above the suction port in the casing, a main shaft to which the impeller is fixed, and a drive mechanism that rotationally drives the main shaft, Via a plurality of discharge valves respectively disposed between the discharge port of the vertical shaft pump and the discharge pipe, and an air flow path in which a control valve is disposed on the suction bell of each vertical shaft pump. A plurality of compressed air supply sources connected to each other, and a water level detecting means for detecting the water level in the water absorption tank. Each of the vertical pumps closes the discharge valve and closes the discharge port and the discharge pipe. Block communication with The control valve is opened, the casing is filled with compressed air from the compressed air supply source, and the driving mechanism rotates the main shaft by the driving mechanism, and the discharge valve is opened. A normal operation in which the discharge port and the discharge pipe are communicated, the control valve is closed, and the main shaft is rotated by the drive mechanism in a state where the supply of the compressed air from the compressed air supply source is stopped; The plurality of vertical shaft pumps are sequentially switched from the forced air operation to the normal operation in response to a rise in the water level in the water absorption tank detected by the water level detection means. I will provide a.

  According to this configuration, each vertical pump of a pump facility including a plurality of vertical pumps is operated in forced air in a state in which the casing is filled with compressed air from the compressed air supply source, and compressed air from the compressed air supply source. Can be switched to the normal operation in a state where the supply to the inside of the casing is stopped. Moreover, according to the rise in the water level in the water absorption tank detected by the water level detection means, the plurality of vertical shaft pumps are switched from the forced air operation to the normal operation in a desired order. Since the water level in each vertical pump can be adjusted by switching from forced air operation to normal operation, impellers of multiple vertical pumps (for example, all vertical pumps) can be operated even when water suddenly flows into the water absorption tank. The plurality of vertical shaft pumps start draining step by step (in order) without being submerged at the same time and starting operation draining. Even when water suddenly flows into the water absorption tank, since a plurality of vertical pumps can start draining stepwise, there is no adverse effect on power supply equipment that supplies power to the drive mechanism due to sudden load fluctuations.

  It is preferable to rearrange the order in which the vertical shaft pump is sequentially switched from the forced air operation to the normal operation for each predetermined period.

  If the order in which a plurality of vertical pumps switch from forced air operation to normal operation according to the rise in the water level in the water absorption tank is constant or unchanged, for example, the vertical pump (water absorption pump that first switches from forced air operation to normal operation) The vertical pump that switches from forced air operation to normal operation when the tank is at a low water level drains frequently, whereas the vertical pump that finally switches from forced air operation to normal drain operation (high in the water absorption tank) The vertical pump that switches from forced air operation to normal operation when the water level is low, the frequency of draining is low. As a result, the progress of the wear of the vertical shaft pump component that is first switched from the forced air operation to the normal operation becomes significant as compared with other vertical shaft pumps. That is, a reduction occurs. However, by rearranging the order of switching from the forced air operation to the normal operation for each predetermined period, the drainage operation time of each vertical shaft pump in a certain period can be made uniform, and the reduction can be eliminated. As a result, the interval between the vertical shaft pumps can be increased, and labor and cost can be reduced.

  Specifically, in the plurality of vertical shaft pumps, the suction port of the suction bell is provided on the same horizontal plane, the impeller is provided at the same height from the suction port, and the water level detecting means is When it is detected that the water level of the water tank is at a preset standby water level lower than the suction port, all the plurality of vertical pumps start operation, and the discharge valves of all the plurality of vertical pumps When the water level detection means detects that the water level of the water tank has reached the same height as the suction port, all the vertical pumps start the forced air operation, and the water level detection means However, when it is detected that the water level of the water absorption tank has reached one of a plurality of different reached water levels set in advance corresponding to each of the plurality of vertical pumps, the vertical pump corresponding to the reached water level Said It is preferable that during the operation Seiki switched to the normal operation.

  According to this configuration, the positions of the suction ports and the impellers of the plurality of vertical pumps are the same, and the same specifications can be used as the plurality of vertical pumps. That is, the specifications of a plurality of vertical shaft pumps can be unified. Therefore, it is not necessary to individually design the vertical shaft pump, and the cost of the entire pump equipment can be suppressed.

  Specifically, the compressed air supply source includes an air tank that stores the compressed air connected by an air passage and a through-hole penetrating the outside and the inside of the suction bell, and the air tank includes the air tank. It is preferable to provide a compressor that supplies compressed air.

  The suction pump of the vertical shaft pump is provided with a downwardly opened upper suction bell provided with the through-hole and an inner side of the upper suction bell, with a lower end on the lower end side of the upper suction bell. The lower suction bell is located below the lower end side tip and is opened downward, and between the upper suction bell and the lower suction bell, the vertical pump below the impeller A flow path may be formed to communicate the inside of the casing and the outside of the casing.

  With this configuration, there are two types of operation states during drainage of each vertical shaft pump, a normal drainage operation and an airlock operation, and it is possible to realize a preliminary standby operation without a hunting operation or an air-water mixing operation. Thereby, the vibration which has a bad influence on a vertical shaft pump can be reduced, and the lifetime of a vertical shaft pump and pump equipment can be extended.

  The vertical shaft pump branches from the air tank and communicates with the bearing means of the main shaft of the vertical pump inside the casing, a flow meter provided in the air flow conduit, and more than the flow meter Branching from the middle of the air duct on the air tank side and connected to the inside of the discharge elbow of the pump, and a differential pressure gauge provided in the pipe for detection, the flow rate A bearing diagnosis device for diagnosing whether or not an abnormality has occurred in the bearing means based on an air flow rate detected by a meter and a differential pressure detected by the differential pressure gauge may be further provided. When a bearing diagnostic device is installed, the air pressure supplied to the gap between the bearing and the main shaft of the pump using a part of the compressed air in the air tank, and the differential pressure between the air supply pressure and the pump discharge pressure Therefore, it is possible to determine an abnormality with accuracy and reliability with a simple configuration.

  The second aspect of the present invention comprises a water absorption tank into which water flows from the upstream side and a suction bell having a suction opening that opens to the water absorption tank on the lower end side, while the discharge port connected to the discharge pipe is located on the upper end side. A plurality of vertical shaft pumps each having a casing provided in the casing, an impeller positioned above the suction port in the casing, a main shaft to which the impeller is fixed, and a drive mechanism that rotationally drives the main shaft, Via a plurality of discharge valves respectively disposed between the discharge port of the vertical shaft pump and the discharge pipe, and an air flow path in which a control valve is disposed on the suction bell of each vertical shaft pump. A plurality of compressed air supply sources connected to each other and a water level detecting means for detecting the water level in the water absorption tank are provided, and each of the vertical shaft pumps closes the discharge valve and closes the discharge port and the discharge pipe. Block communication with The control valve is opened, the casing is filled with compressed air from the compressed air supply source, and the driving mechanism rotates the main shaft by the driving mechanism, and the discharge valve is opened. A normal operation in which the discharge port and the discharge pipe are communicated, the control valve is closed, and the main shaft is rotated by the drive mechanism in a state where the supply of the compressed air from the compressed air supply source is stopped; The pump equipment is characterized in that the plurality of vertical shaft pumps are sequentially switched from the forced air operation to the normal operation in response to a rise in the water level in the water absorption tank detected by the water level detection means. This is the driving method.

  According to the pump equipment of the present invention, even when abrupt water flows into the water absorption tank, by realizing the stepwise drainage start of the plurality of vertical pumps, the power supply equipment that supplies power to the drive mechanism of each vertical pump It is possible to prevent adverse effects caused by sudden load fluctuations. Further, since the drainage operation time of each vertical pump can be made uniform, the interval between the vertical pumps can be increased, and labor and cost can be reduced. Furthermore, since the specifications of a plurality of vertical pumps can be unified, it is not necessary to individually design the vertical pumps, and the cost of the pump equipment as a whole can be reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a pump facility 10 according to the present invention. The pump facility 10 includes a plurality of (three in this embodiment) preceding standby vertical pumps (hereinafter simply referred to as pumps) 11A to 11C having the same specifications. Each of the pumps 11A to 11C includes an air tank 12, a compressor 13, a bearing diagnostic device 14, a compressed air supply line 15, a compressed air filling line 16, a blower line 17, a detection line 18, a control unit 19, and a suction unit. A water tank 20 is provided. The compressor 13 and the air tank 12 constitute a compressed air supply source, and the compressed air supply line 15 and the compressed air filling line 16 constitute an air flow path. When it is not necessary to distinguish the pumps 11 </ b> A to 11 </ b> C in particular, they are simply expressed as the pump 11.

  The pump 11A is for draining water such as rainwater flowing into the water absorption tank 20 of the drainage pump station from an inflow side (upstream side) pipeline (not shown) to the downstream side, and includes a casing 22 extending in the vertical direction. ing. The casing 22 includes a straight tubular pumping pipe 22a, a pump casing 22b connected to the lower end of the pumping pipe 22a, and a discharge elbow 22c connected to the upper end of the pumping pipe 22a and curved in the horizontal direction from the vertical direction. A discharge pipe 23 is connected to the discharge elbow 22 c through a discharge valve 29. An impeller 24 is disposed in the pump casing 22. A main shaft 25 to which the impeller 24 is fixed at the lower end extends in the vertical direction and protrudes outside the casing 22. The main shaft 25 is supported by non-water-filled bearings (bearing means) 26 and 27 (hereinafter simply referred to as bearings) that function as radial bearings. The bearing 26 is attached to a rib 26a protruding from the inner surface of the pump casing 22b, and the bearing 27 is attached to a rib 27a protruding from the inner surface of the pumped pipe 22a. The upper end side of the main shaft 25 is connected to a drive mechanism 28 including a motor, a speed reduction mechanism and the like which are schematically shown.

  An upper suction bell 31 and a lower suction bell 32 are provided on the lower end side of the pump casing 22 b, that is, the lowermost portion of the casing 22. First, the upper suction bell 31 is opened downward, and its upper end side is connected to the lower end side of the pump casing 22b. The upper suction bell 31 has a diameter that increases from the upper end to the lower end, and the lower end tip 31a extends in the horizontal direction.

  Inside the upper suction bell 31, a lower suction bell 32 having upper and lower ends opened is disposed. The outer periphery of the lower suction bell 32 is disposed with a space from the inner peripheral surface of the upper suction bell 31, and both constitute a so-called dual structure suction bell. Similar to the upper suction bell 31, the lower suction bell 32 has a diameter increasing from the upper end toward the lower end, and the lower end side tip portion 32 a extends in the horizontal direction. The lower end side tip portion 32 a of the suction bell 32 is located below the lower end side tip portion 31 a of the upper suction bell 31. Therefore, there is a height difference α between the lower surface 31b of the lower end tip 31a of the upper suction bell 31 and the lower surface 32b of the lower end tip 32a of the lower suction bell 32 (see FIGS. 9 to 11).

  As described above, the lower suction bell 32 is spaced from the upper suction bell 31, so that the cross section is circular between the inner peripheral surface of the upper suction bell 31 and the outer peripheral surface of the lower suction bell 32. An annular flow path 33 is formed. In the flow path 33, the upper end side opening 33 a is located in the upper suction bell 31, and the lower end side opening 33 b is formed by the lower end side tip portions 31 a and 32 a of the upper suction bell 31 and the lower suction bell 32. Therefore, the inside of the casing 22 below the impeller 24 and the outside of the casing 22 communicate with each other by the flow path 33. As shown in FIG. 2, the lower suction bell 32 is fixed to the upper suction bell 31 by providing a rib 35 that connects the upper suction bell 31 and the lower suction bell 32. On the side surface of the upper suction bell 31, a through-hole 36 that penetrates the inner side and the outer side of the casing 22 in the horizontal direction is provided within the range of the width of the connected rib 35 in the vertical direction. Near the upper end of the lower suction bell 32, there are provided a plurality of through holes 38 that allow the compressed air supplied from the through holes 36 to be quickly filled into the casing 22. Further, a flow path penetrating the through hole 36, the rib 35, and the through hole 38 may be provided and connected to the compressed air filling conduit 16.

  In the pumps 11A to 11C, the suction port of the suction bell 31 is provided on the same horizontal plane, and the impeller 24 is provided at the same height from the suction port.

  The air tank 12 stores compressed air supplied from the compressor 13. The air tank 12 is connected to the through-hole 36 of the upper suction bell 31 of the pump 11 and the compressed air filling pipe line 16 via a control valve 37.

  The compressor 13 is connected to the air tank 12 and the compressed air supply line 15 via a check valve 39.

  The control device 19 is connected to a control valve 37 of the compressed air filling pipeline 16 of the plurality of pumps 11, a discharge valve 29 of the pump 11, and a water level meter (water level detection means) 46 provided in the water absorption tank 20. The control device 19 controls the opening and closing of the control valve 37 and the discharge valve 29 of the pump 11 according to the detected value of the water level gauge 46 of the water absorption tank 20.

  FIG. 3 shows an example of the flow rate-head curve (HQ curve) of the pump 11 together with the efficiency η and the power L. In FIG. 3, the horizontal axis represents the ratio of the flow rate Q to the optimum flow rate Qopt (Q / Qopt), and the vertical axis represents the ratio of the lift head H to the optimum lift Hopt (H / Hopt). The range where Q / Qopt is about 0.6 to 1.2 is the rated operation region, the Q / Qopt is about 1.2 or more is the excessive flow region, and the Q / Qopt is about 0.6 or less is the partial flow region.

  Next, as for the operation method of the pump facility 10 according to the present invention, for example, as shown in FIG. 1, a case where a plurality of pumps 11 are operated in the order of ABC with three units A, B, and C will be described. In addition, it is possible to operate in the order of ACB, BAC, BCA, CAB, and CBA. However, the operation is the same except that the operation start order of the pumps is different, so only an example is shown.

  The water level meter 46 of the water absorption tank 20 is a preset standby water level in which the water level of the water absorption tank 20 is lower than WL1 (the same height (WL3) as the lower end opening (suction port) of the upper suction bell 31). When it is detected that there is no water in the inside), the detected value is transmitted to the control device 19. The control device 19 transmits an operation signal to the plurality of pumps 11A to 11C and starts operation. Since there is no water in the pump casings 22b of the pumps 11A to 11C, the impellers 24A to 24C rotate in the air (idling operation). The control device 19 also transmits an operation signal to the discharge valves 29A to 29C of the plurality of pumps 11A to 11C, and closes the discharge valves 29A to 29C.

  When the water level of the water absorption tank 20 is not less than WL1 and less than WL3, the control valves 37A to 37C of the compressed air filling lines 16A to 16C of all the pumps 11A to 11C are kept closed, and the pumps 11A to 11A are closed. Air is not sent to all of 11C. (At the end of the previous operation of the pumps 11A to 11C, the control valves 37A to 37C of the compressed air filling pipes 16A to 16C of all the pumps 11A to 11C are closed, so nothing is performed here. .) The discharge valves 29A to 29C of all the pumps 11A to 11C are kept closed.

  As shown in FIG. 4, when the water level meter 46 of the water absorption tank 20 detects that the water level of the water absorption tank 20 has reached WL <b> 3, the detected value is transmitted to the control device 19. The control device 19 transmits an operation signal to all of the plurality of pumps 11A to 11C, and opens all the control valves 37A to 37C of the compressed air filling lines 16A to 16C. Thereby, compressed air of air tanks 12A-12C is sent into the inside of casings 22A-22C through penetration holes 36A-36C of upper suction bells 31A-31C of pumps 11A-11C. The discharge valves 29A to 29C of all the pumps 11A to 11C are kept closed. Here, the operation in this state, that is, the discharge valve 29 is closed, the communication between the discharge port and the discharge pipe 23 is blocked, the control valve 37 is opened, and the casing 22 is supplied with a compressed air supply source. The operation in which the main shaft 25 is rotated by the drive mechanism 28 in a state where the compressed air is filled is referred to as forced air operation.

  When the water level in the water absorption tank 20 is lower than WL3 or higher and WL4 (the drainage start water level above the impeller 24 in the casing 22 where the first pump (in this example, 11A) starts draining), the pump Compressed air is filled from the lower end opening of the upper suction bells 31A to 31C in the casings 22A to 22C of 11A to 11C to the discharge valves 29A to 29C at the tip of the discharge elbow 22c.

  As shown in FIG. 5, when the water level meter 46 of the water absorption tank 20 detects that the water level of the water absorption tank 20 has reached WL4, the detected value is transmitted to the control device 19. The control device 19 transmits an operation signal to the pump 11A, closes the control valve 37A of the compressed air filling line 16A, and opens the discharge valve 29A of the pump 11A. Accordingly, when the supply of compressed air to the pump 11A is stopped, the water reaches above the impeller 24, so that pumping and draining of the pump 11A is started (normal operation).

  When the water level of the water absorption tank 20 is lower than WL4 and lower than WL5 (the drainage start water level adjacent to the second pump (in this example, 11B) above WL4 where drainage starts), only the pump 11A performs normal operation. The pumps 11B and 11C continue the forced air operation.

  As shown in FIG. 6, when the water level meter 46 of the water absorption tank 20 detects that the water level of the water absorption tank 20 has reached WL5, the detected value is transmitted to the control device 19. The control device 19 transmits an operation signal to the pump 11B, closes the control valve 37B of the compressed air filling line 16B, and opens the discharge valve 29B of the pump 11B. As a result, the supply of compressed air to the pump 11B is stopped, so that pumping and draining of the pump 11B are started.

  When the water level in the water absorption tank 20 is lower than WL5 and lower than WL6 (the drainage start water level adjacent to the third pump (in this example, 11C) above WL5 where drainage starts), the pumps 11A and 11B are operated normally. The pump 11C continues the forced air operation.

  As shown in FIG. 7, when the water level meter 46 of the water absorption tank 20 detects that the water level of the water absorption tank 20 has reached WL 6, the detected value is transmitted to the control device 19. The control device 19 transmits an operation signal to the pump 11C, closes the control valve 37C of the compressed air filling line 16C, and opens the discharge valve 29C of the pump 11C. As a result, the supply of compressed air to the pump 11C is stopped, so that pumping and draining of the pump 11C are started.

  When the water level of the water absorption tank 20 is WL6 or more, all the pumps 11A to 11C are performing normal operation.

  With reference to FIGS. 8 to 12, the state of one pump 11 will be described in relation to the water level of the water absorption tank 20. When the water level in the water absorption tank 20 is higher than the drainage water level WL4 above the impeller 24 in the casing 22 as shown in the state 8-1 in FIG. The discharged water is discharged into the discharge pipe 23 (normal operation). The operation state of the pump 11 in the normal operation at the height of the drainage water level WL4 or higher is the rated operation area A or the excessive flow area C (see FIG. 3). In the rated operation area A, as shown in FIG. 9, water is sucked up from the lower end opening of the lower suction bell 32, but the inflow of water from the flow path 33 between the upper suction bell 31 and the lower suction bell 32 is Absent. On the other hand, in the excessive flow region C, water is sucked into the casing 22 from both the lower end opening of the lower suction bell 32 and the lower end opening 33b of the flow path 33 as shown in FIG. In any case, the air flow from the flow path 33 into the casing 22 does not flow because the lower end opening 33b of the flow path 33 is submerged during normal operation at a height equal to or higher than the drainage water level WL4. Even if the water level drops from the height of the drainage water level WL4 or higher, the water level WL3 of a height corresponding to the lower surface 31b of the lower end side tip portion 31a of the upper suction bell 31 (as will be described later, this water level is The normal operation in the rated operation area A or the excessive flow area C is maintained until the re-drainage start water level is reached.

  As shown in state 8-2, when the water level drops to the water level WL3, the operation state of the pump 11 becomes the partial flow region B (see FIG. 3). Therefore, as shown in FIG. 11, the backflow water from the impeller 24 flows out of the casing 22 from the upper end opening 33 a of the flow path 33 through the lower end opening 33 b. Since there is backflow water passing through the flow path 33, air does not flow from the flow path 33 into the casing 22, and normal operation is maintained.

  Further, in the water level region from the normal drain operation to the air lock operation described later, the water accumulated in the flow path 33 by the water flowing backward from the impeller 24 and flowing outside the casing 22 through the flow path 33. Garbage etc. is washed out of the casing. That is, the flow path 33 is automatically washed by the backflow water.

  There is a drop in water level corresponding to the height difference α between the upper suction bell 31 and the lower suction bell 32 from the water level WL3, and the water level (drainage stop water level WL2) corresponding to the lower surface 32b of the lower end tip portion 32a of the lower suction bell 32 is reached. When it reaches, a large amount of air is instantaneously sucked into the region below the impeller 24 in the casing 22 from near the water surface through the lower end opening of the lower suction bell 32 as shown in the state 8-3. As a result, as shown in state 8-4, an air pool 64 is formed in a region below the impeller 24 in the casing 22, and a water column 65 is formed above the impeller 24 (air lock operation). . At the time of the air lock operation, as shown in FIG. 12, a small amount of air sucked from the lower end opening 33b of the flow path 33 flows into the air reservoir 64 from the upper end opening 33a. The air lock operation is maintained by supplying air to the air reservoir 64.

  When the water level in the water absorption tank 20 rises from the drainage stop water level WL2 and rises to a position (redrainage start water level WL3) corresponding to the lower surface 31b of the lower end tip 31a of the upper suction bell 31 as shown in state 8-5. Since the lower end opening 33b of the flow path 33 is closed with water, the inflow of air through the flow path 33 is stopped, and the pumping by the impeller 24 is resumed so that the normal drainage operation is performed.

  In the pump 11 described above, when the water level drops to the water level WL3 corresponding to the lower surface 31b of the lower end 31a of the upper suction bell 31, the backflow water from the impeller 24 passes through the flow path 33 and the casing 22. Flows from inside to outside. Therefore, inflow of air into the casing 22 via the flow path 33 does not occur in this water level region. Further, when the water level drops to the drainage stop water level WL2 corresponding to the lower surface 32b of the lower end tip 32a of the lower suction bell 32, a large amount of air near the water surface is sucked into the casing 22 from the lower suction bell 32 instantaneously. An air pool 64 is formed, and air flows into the air pool 64 through the flow path 33, so that the air lock operation is maintained. Furthermore, when the water level rises to the re-drainage start water level WL3 corresponding to the lower surface 31b of the lower end tip 31a of the upper suction bell 31, the flow path 33 is closed by water, so that the inflow of air into the casing 22 is stopped. The drainage is resumed. In other words, air flows into the casing 22 through the flow path 33 during the air lock operation, but the flow path 33 is closed with water in the water level region before and after the transition to the air lock operation. There is no inflow of air. Accordingly, there are two types of operation states of the pump 11: normal drain operation and air lock operation. The air standby operation and the preceding standby operation without the hunting operation and the air / water mixed drain operation in which the normal drain operation is repeated in a very short time. Can be realized.

  Next, in the pump facility 10 according to the present invention using a plurality of the pumps 11 described above, when the water level of the water absorption tank 20 is lowered after the start of pumping, all of the pumps 11A to 11C at the immediately preceding highest water level. The states of the pumps 11A to 11C are maintained as they are.

  When the water level in the water absorption tank 20 drops to a position not lower than the height of WL2 after the start of pumping and the water level rises again, the water level in the water absorption tank 20 is higher than the drainage start water level set in advance for any pump 11X. Even if it exists below, the operation | movement of the pump installation 10 is the same as that of the said description except the point which is maintaining the state of the pump 11X in the last highest water level.

  When the water level of the water absorption tank 20 drops to a position lower than the height of WL2 after the start of pumping and the water level rises again, the water level of the water absorption tank 20 does not become lower than the height of WL2 and rises from the water level of WL2. Is as described above. Moreover, even if the water level of the water absorption tank 20 becomes lower than the height of WL2 and the water level rises again, the use of the pump 11 causes all the pumps 11A to 11C to similarly perform the normal drain operation or the air lock operation as described above. Only one of the operations is performed. As a result, it is possible to avoid causing the pump 11 to perform the hunting operation and the air / water mixed drainage operation.

  Moreover, in the pump installation 10 concerning this invention, when the water level of the water absorption tank 20 falls after a pumping start, you may stop the pumps 11A-11C in order according to the preset water level.

  The vertical shaft pump facility 10 of the present embodiment has the following effects.

  According to this configuration, the vertical pump 11 of the pump facility 10 including the plurality of vertical pumps 11 is operated in the forced air in a state where the casing 22 is filled with the compressed air from the compressed air supply source, and the compressed air supply source. It is possible to switch between normal operation in a state where supply of compressed air from the inside to the casing 22 is stopped. Moreover, according to the raise of the water level in the water absorption tank 20 which the water level detection means 46 detects, the several vertical shaft pump 11 switches from forced air operation to normal operation in a desired order. Since the water level in each vertical pump 11 can be adjusted by switching from forced air operation to normal operation, even when water suddenly flows into the water absorption tank 20, a plurality of vertical pumps 11 (for example, all the vertical pumps 11). The impellers 24 are not submerged at the same time, and the operation drainage is not started. The plurality of vertical shaft pumps 11 start draining step by step (in order). Even when water suddenly flows into the water absorption tank 20, since a plurality of vertical pumps 11 can start gradual drainage, there is no adverse effect on power supply equipment that supplies power to the drive mechanism 28 due to sudden load fluctuations. .

  That is, even when abrupt water flows into the water absorption tank 20, a sudden load is applied to the power supply equipment that supplies power to the drive mechanism 28 of each vertical pump 11 by realizing the stepwise drainage of the vertical pumps 11. It is possible to prevent adverse effects caused by fluctuations.

  If the order in which the plurality of vertical pumps 11 are switched from the forced air operation to the normal operation according to the rise in the water level in the water absorption tank 20 is constant or unchanged, for example, the vertical pump that first switches from the forced air operation to the normal operation. (Vertical pump 11 that switches from forced air operation to normal operation when water tank 20 is at a low water level) drains frequently, whereas vertical pump 11 that finally switches from forced air operation to normal drain operation ( The vertical shaft 11) that switches from the forced air operation to the normal operation when the inside of the water absorption tank 20 is at a high water level is less frequently discharged. As a result, the progress of wear of components such as the bearings 26 and 27 and the impeller 24 of the vertical shaft 11 that first switches from the forced air operation to the normal operation becomes significant as compared with the other vertical pumps 11. That is, a reduction occurs. However, by rearranging the order of switching from the forced air operation to the normal operation every predetermined period, the drainage operation time of each vertical shaft pump 11 in a certain period can be made uniform, and the reduction in the amount can be eliminated. As a result, the interval between the vertical shaft pumps 11 can be increased, and labor and cost can be reduced.

  That is, since the drainage operation time of each vertical shaft pump 11 can be made uniform, the interval between replacements of the vertical shaft pumps 11 becomes long, and labor and cost can be suppressed.

  According to this configuration, the suction ports of the plurality of vertical pumps 11 and the positions of the impellers 24 are the same, and the plurality of vertical pumps 11 having the same specifications can be used. That is, the specifications of the plurality of vertical shaft pumps 11 can be unified. Therefore, it is not necessary to design the vertical pump 11 individually, and the cost of the pump equipment 10 as a whole can be suppressed.

  Next, the bearings 26 and 27 of the pump 11 and the bearing diagnostic device 14 for the bearings 26 and 27 will be described.

  Since the two bearings 26 and 27 have the same structure, the bearing 27 will be described with further reference to FIGS. 13 and 14. The bearing 27 includes a bearing casing 51 having openings at both ends, and the bearing casing 51 is fixed to the rib 27a. In the bearing casing 51, two bearing bodies 52a and 52b arranged in the bearing direction of the main shaft 25 are provided. Each of the bearing bodies 52a and 52b includes a cylindrical shell 53 having openings at both ends fixed to the inner peripheral wall of the bearing casing 51, and a plurality of segment-like sliding bodies 54 attached to the inner peripheral surface side of the shell 53. ing. The shell 53 is made of, for example, stainless steel, copper alloy, synthetic resin, or the like. The sliding body 54 is made of resin or metal material. At both ends of the bearing casing 51, annular end plates 55a, 55b for holding the bearing bodies 52a, 52b are attached.

  Since the bearing bodies 52 a and 52 b are arranged at intervals in the axial direction of the main shaft 25, a cylindrical air chamber 56 is formed in the bearing casing 51 between the bearing bodies 52 a and 52 b. An air hole 51 a penetrating the bearing casing 51 is provided, and the air chamber 56 communicates with the outside of the bearing 27 through the air hole 51 a.

  The bearing diagnostic device 14 includes a bearing 27 of the pump 11, a blower pipe 17, a detection pipe 18, a flow meter 43 and a differential pressure gauge 44.

  The air duct 17 is connected to the air chamber 56 of the bearing 27 from the outlet of the air tank 12. The air duct 17 is provided with a flow meter 43 for detecting the air flow rate. Further, a check valve 58 is provided in the air duct 17. By opening and closing the check valve 58, the air duct 17 can be communicated or blocked.

  The detection pipe 18 branches from the middle of the blower pipe 17 on the air tank 12 side of the flow meter 43 and is connected to the inside of the discharge elbow 22 c of the pump 11. A differential pressure gauge 44 is provided in the detection pipeline 18. The differential pressure gauge 44 detects the differential pressure between the air supply pressure of the air tank 12 and the discharge pressure of the pump 11.

  The control device 19 in FIG. 1 has an abnormality in the sliding body 54 of the non-water-filled bearings 27A to 27C based on the function of controlling the check valves 58A to 58C and the signals from the flow meters 43A to 43C and the differential pressure gauges 44A to 44C. It also has a function of diagnosing the occurrence.

  Next, the principle of abnormality detection of the bearings 27A to 27C of the pump facility 10 according to the present invention will be described. The compressed air supplied from the compressor 13 is supplied to the air chambers 56A to 56C of the bearings 27A to 27C via the air ducts 17A to 17C. The air supplied to the air chambers 56 </ b> A to 56 </ b> C is a slight gap between each sliding body 54 and the outer peripheral surface of the main shaft 25 and a gap 57 a between the sliding bodies 54 adjacent to each other (hereinafter, these are collectively referred to as bearings 27 </ b> A to 27 </ b> A ”). 27C and a clearance 57 between the main shafts 25A to 25C), and flows into the casing 22 and is discharged to the discharge elbow 22c. The flow rate of air flowing through the gaps 57A to 57C between the bearings 27A to 27C and the main shafts 25A to 25C corresponds to the flow rate of air flowing through the air ducts 17A to 17C detected by the flow meters 43A to 43C. . On the other hand, a differential pressure between the compressed air supply pressure supplied from the compressed air supply source 13 and the discharge pressure of the pump 11 is detected by a differential pressure gauge 44.

  Here, there is a relationship as shown in FIG. 15 between the air flow rate detected by the flow meters 43 </ b> A to 43 </ b> C and the differential pressure detected by the differential pressure meter 44. 15, a1 is a design value when the gap 57 between the sliding body 54 and the main shaft 25 is a design value, a2 is a case where the gap 57 between the sliding body 54 and the main shaft 25 is enlarged to some extent due to wear of the sliding body 54, and a3 is a sliding motion. When the gap 57 between the sliding body 54 and the main shaft 25 is expanded to the extent that the sliding body 54 needs to be replaced due to the wear of the moving body 54, a4 indicates the case where the sliding body 54 is damaged. The point that the air flow rate increases when the differential pressure increases is the same in any of a1 to a4. However, when the differential pressure is the same value, the air flow rate is in the order of a4, a3, a2, a1. large. Therefore, if the air flow rate corresponding to a3 in FIG. 15 is set as the first threshold value, the air flow rate measured by the flow meters 43A to 43C is compared with the first threshold value, so that there is an exchange. The wear of the sliding body 54 can be determined. In addition, if the air flow rate corresponding to a4 in FIG. 15 is set to the second threshold value, the damage of the sliding body 54 is determined by comparing the air flow rate measured by the flow meters 43A to 43C with this threshold value. can do.

  For example, when diagnosing wear or breakage of the bearing 27A, the check valve 58A is opened, and the compressed air from the air tank 12A to the gap 57A between the bearing 27A and the main shaft 25A via the air duct 17A. Introduce it. Then, the control device 19 compares the amount of air flowing through the air duct 17A detected by the flow meter 43A with the differential pressure detected by the differential pressure gauge 44A. In FIG. 15, when the differential pressure detected by the differential pressure gauge 44 is dP1, the control device 19 allows the sliding body 54 to a degree that requires replacement if the air flow rate detected by the flow meter 43A exceeds the first threshold value FTH1. It is determined that the wear of the sliding body 54 is progressing, and if the second threshold value FTH2 is exceeded, it is determined that the sliding body 54 is damaged.

  Since the controller 19 determines the occurrence of an abnormality in the bearings 27A to 27C based on the air flow detected by the flow meters 43A to 43C and the differential pressure detected by the differential pressure gauges 44A to 44C, the bearing temperature detected by the temperature sensor. In addition, the determination can be made more accurately than in the case where the occurrence of abnormality is indirectly determined based on the vibration detected by the vibration sensor. Specifically, when a thermocouple is used as a temperature sensor, there is a high possibility of occurrence of an abnormal signal or failure due to disconnection, but abnormal signal generation or failure is possible by using flow meters 43A to 43C and differential pressure gauges 44A to 44C. Can be reduced.

  FIG. 16 shows the relationship (HQ curve) between the flow rate of the pump 11 and the discharge pressure (lift). The flow rate region of F1 or higher is a normal drainage operation state in which the water level in the water absorption tank 20 is above the impeller 24. In this normal drainage operation state, only water sucked up from the water absorption tank 20 is discharged from the discharge elbow 22c. The point b0 where both the flow rate and the discharge pressure are zero is a so-called air lock operation, where an air pool is formed in a region below the impeller 24 in the casing 22, and a water column is formed in a region above the impeller 24. Is done. In this air lock operation state, the bubbles rise from the air pool to the water column, so that intense vibration occurs. The flow rate region below F1 is the air / water mixing operation state in which the water level in the water absorption tank 20 does not reach the impeller 24. As described above, the pump 11 of the pump facility 10 according to the present invention is in the air / water mixing operation state. Can be avoided.

  In the airlock operation state, vibration occurs due to gas mixing regardless of whether or not an abnormality has occurred in the bearings 27A to 27C. Therefore, it is difficult for the vibration sensor to accurately determine the abnormality of the bearing. However, in this embodiment, since abnormality is determined based on the differential pressure measured by the differential pressure gauges 44A to 44C and the air flow rate detected by the flow meters 43A to 43C, the air lock operation in which severe vibration has occurred. Even in the state, the abnormality of the bearings 27A to 27C can be accurately determined. In addition, the bearings 27 </ b> A to 27 </ b> C can be cooled and cleaned by blowing compressed air through the air duct 17.

  Referring to FIG. 16, the point b1 is in the normal drainage operation state, and the discharge pressure of the pump 11 is P1. At this time, the air supply pressure CP1 needs to be set larger than the discharge pressure P1 by a desired differential pressure dP. Therefore, the control device 19 preferably adjusts the air supply pressure from the compressed air supply source 13 according to the discharge pressure of the pump 11. For example, the control device 19 adjusts the air supply pressure from the compressed air supply source 13 so that the differential pressure detected by the differential pressure gauge 44 is always constant.

  The present invention has been described according to the embodiment so far, but the present invention is not limited to the embodiment, and various modifications are possible. For example, when it is assumed that the water level of the water absorption tank 20 becomes WL6 or higher and another pump is required in addition to the pumps 11A to 11C, a desired number of pumps may be added in advance. it can.

The figure which shows the pump installation concerning this invention. II-II sectional view taken on the line of FIG. The figure which shows the flow volume-head curve of a pump. The figure which shows the state of pump equipment when the water level of a water absorption tank reaches WL3. The figure which shows the state of pump equipment when the water level of a water absorption tank reaches WL4. The figure which shows the state of pump equipment when the water level of a water absorption tank reaches WL5. The figure which shows the state of pump equipment when the water level of a water absorption tank reaches WL6. Schematic which shows transition of the operating state of a vertical shaft pump. The fragmentary sectional view which shows the flow of the water in the upper part and the lower suction bell in a rated operation area. The fragmentary sectional view which shows the flow of the water in the upper part and the lower suction bell in an excessive flow area. The fragmentary sectional view which shows the flow of the water in the upper part and the lower suction bell in a partial flow area. The fragmentary sectional view which shows the flow of the air in the upper part and the lower suction bell at the time of an air lock driving | operation. The longitudinal cross-sectional view which shows a non-water-filled bearing. Sectional drawing in the XIV-XIV line | wire of FIG. The diagram which shows roughly the relationship between a differential pressure | voltage and an air flow rate. The diagram which shows roughly the relationship between the flow volume of a vertical shaft pump, and discharge pressure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Pumping equipment 11 Vertical shaft pump 12 Air tank 13 Compressed air supply source 14 Bearing diagnostic device 15 Compressed air supply line 16 Compressed air filling line 17 Blowing line 18 Detection line 19 Control unit 20 Water absorption tank 22 Casing 22a Pumping water Pipe 22b Pump casing 22c Discharge elbow 23 Discharge pipe 24 Impeller 25 Main shaft 26, 27 Bearing (bearing means)
26a, 27a Rib 28 Drive mechanism 29 Discharge valve 31 Upper suction bell 31a, 32a Lower end tip 31b, 32b Lower surface 32 Lower suction bell 33 Channel 33a Upper end opening 33b Lower end opening 35 Rib 36 Through hole 37 Control valve 38 Through Hole 39 Check valve 43 Flow meter 44 Differential pressure gauge 46 Water level gauge (water level detection means)
51 Bearing casing 51a Air hole 52a, 52b Bearing body 53 Shell 54 Sliding body 55a, 55b End plate 56 Air chamber 58 Check valve 64 Air pool 65 Water column

Claims (7)

A water absorption tank into which water flows from the upstream side;
A casing provided with a suction bell having a suction opening that opens in the water absorption tank on the lower end side, a casing provided with a discharge outlet connected to a discharge pipe on the upper end side, and an impeller positioned above the suction opening in the casing; A plurality of vertical shaft pumps each having a main shaft to which the impeller is fixed and a drive mechanism that rotationally drives the main shaft;
A plurality of discharge valves respectively disposed between the discharge port and the discharge pipe of each vertical shaft pump;
A plurality of compressed air supply sources each connected via an air flow path in which a control valve is disposed on the suction bell of each of the vertical shaft pumps;
Water level detecting means for detecting the water level in the water absorption tank,
Each said vertical shaft pump
With the discharge valve closed, the communication between the discharge port and the discharge pipe is shut off, the control valve is opened, and the casing is filled with compressed air from the compressed air supply source. Forced air operation to rotate the spindle by the drive mechanism;
The discharge valve is opened, the discharge port and the discharge pipe are communicated, the control valve is closed, and the supply of compressed air from the compressed air supply source is stopped by the drive mechanism. The normal operation of rotating the spindle can be switched, and
The pump equipment, wherein the plurality of vertical pumps are sequentially switched from the forced air operation to the normal operation in response to a rise in the water level in the water absorption tank detected by the water level detection means.   2. The pump equipment according to claim 1, wherein an order in which the vertical shaft pump is sequentially switched from the forced air operation to the normal operation is rearranged for each predetermined period. In the plurality of vertical shaft pumps, the suction port of the suction bell is provided on the same horizontal plane, and the impeller is provided at the same height from the suction port,
When the water level detection means detects that the water level of the water absorption tank is at a preset standby water level lower than the suction port, all the plurality of vertical pumps start operation, and all the plurality of the plurality of vertical pumps The discharge valve of the vertical shaft is closed,
When the water level detection means detects that the water level of the water absorption tank has reached the same height as the suction port, all the vertical shaft pumps start the forced air operation,
When the water level detecting means detects that the water level of the water absorption tank has reached one of a plurality of different reaching water levels set in advance corresponding to each of the plurality of vertical pumps, the water level detecting means corresponds to the reaching water level. The pump installation according to claim 1 or 2, wherein the vertical shaft pump is switched from the forced air operation to the normal operation.   The compressed air supply source includes a through-hole penetrating the outside and the inside provided in the suction bell, an air tank storing the compressed air connected by the air flow path, and supplying the compressed air to the air tank. The pump equipment according to any one of claims 1 to 3, further comprising a compressor.   The suction pump of the vertical shaft pump is provided with a downwardly opened upper suction bell provided with the through-hole and an inner side of the upper suction bell, with a lower end on the lower end side of the upper suction bell. The lower suction bell is located below the lower end side tip and is opened downward, and between the upper suction bell and the lower suction bell, the vertical pump below the impeller The pump equipment according to claim 4, wherein a flow path for communicating the inside of the casing and the outside of the casing is formed.   The vertical shaft pump branches from the air tank and communicates with the bearing means of the main shaft of the vertical pump inside the casing, a flow meter provided in the air flow conduit, and more than the flow meter Branching from the middle of the air duct on the air tank side and connected to the inside of the discharge elbow of the pump, and a differential pressure gauge provided in the pipe for detection, the flow rate 5. The bearing diagnosis apparatus according to claim 4, further comprising a bearing diagnosis device that diagnoses whether or not an abnormality has occurred in the bearing means based on an air flow rate detected by a gauge and a differential pressure detected by the differential pressure gauge. Pump equipment. A water absorption tank into which water flows from the upstream side;
A casing provided with a suction bell having a suction opening that opens in the water absorption tank on the lower end side, a casing provided with a discharge outlet connected to a discharge pipe on the upper end side, and an impeller positioned above the suction opening in the casing; A plurality of vertical shaft pumps each having a main shaft to which the impeller is fixed and a drive mechanism that rotationally drives the main shaft;
A plurality of discharge valves respectively disposed between the discharge port and the discharge pipe of each vertical shaft pump;
A plurality of compressed air supply sources each connected via an air flow path in which a control valve is disposed on the suction bell of each of the vertical shaft pumps;
Water level detecting means for detecting the water level in the water absorption tank, and
Each said vertical shaft pump
With the discharge valve closed, the communication between the discharge port and the discharge pipe is shut off, the control valve is opened, and the casing is filled with compressed air from the compressed air supply source. Forced air operation to rotate the spindle by the drive mechanism;
The discharge valve is opened, the discharge port and the discharge pipe are communicated, the control valve is closed, and the supply of compressed air from the compressed air supply source is stopped by the drive mechanism. The normal operation of rotating the spindle can be switched, and
An operation method of pump equipment, wherein the plurality of vertical pumps are sequentially switched from the forced air operation to the normal operation in response to a rise in the water level in the water absorption tank detected by the water level detection means.

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